The present invention relates to a lamp unit assembling method and a lamp unit mounting structure for mounting a lamp unit, such as a room lamp, in a lamp mounting window of an interior wall member, such as a roof trim, which covers a vehicle body panel.
Generally, when lamp units, such as a room lamp and a courtesy lamp, are mounted on interior wall members, such as a roof trim and a door trim, each of the lamp units is mounted in a corresponding one of lamp mounting windows opened in the interior wall members.
FIGS. 23 and 24 are a perspective view and a sectional view illustrating a related automobile roof assembling method disclosed in Japanese Unexamined Utility Model Publication Hei. 4-57454 and a related lamp unit assembling structure disclosed in Japanese Unexamined Patent Publication Hei. 5-131882, respectively. As shown in FIG. 23, a roof harness 37 is first mounted under a body roof 2 serving as a body panel of a vehicle body 1. Subsequently, a roof trim 30 serving as an interior wall member for covering the body roof 2 is mounted thereunder.
Further, connectors 40 and 41 of the room harness 37 are temporarily and downwardly drawn together with cables 37a and 37b out of a room lamp mounting window 31a and a map lamp mounting window 31b, which serve as the lamp mounting windows opened in the roof trim 30, and then connected to the lamp units, such as the room lamp 35 and the map lamp 36, respectively. Subsequently, the cables 37a and 37b are placed on the roof trim 30 through a room lamp mounting window 31a and a map lamp mounting window 31b. Then, the room lamp 35 and the map lamp 36 are respectively mounted in the room lamp mounting window 31a and the map lamp mounting window 31b by screwing. Finally, non-electric components, such as a rearview mirror 38 and a sun visor 39, are mounted on the roof trim 30. Thus, an automobile roof is assembled.
For example, the room lamp 35 serving as the lamp unit mainly comprises a housing 34, a bulb (that is, an electric bulb) 44, and a cover lens 33, as shown in FIG. 24. The bulb 44 is inserted into between bus bars 43, 43 serving as bulb contacts fixed to the housing 34. One of the bus bars 43, 43 is connected to a room-lamp-side connector 45. A tapping screw 42 for fixing the room lamp 35 to the roof trim 30 is mounted to the housing 34. A mounting hole 32, into which the tapping screw 42 is inserted, is provided in the roof trim 30.
Moreover, a switch unit (not shown), which accommodates a switch circuit connected to the bus bar 43 and is enabled to switch between ON and OFF states of the bulb 44, is attached to the room lamp 35. Furthermore, according to the specification of a vehicle, a reflector designed in consideration of the luminous intensity distribution of the bulb 44 may be attached to a vehicle body panel side portion of the housing 34 in addition to the aforementioned constituent elements.
FIG. 25 is a schematic view illustrating a mounting structure for related lamp units disclosed in Japanese Unexamined Patent Publication Hei. 1-307108. FIG. 26 is a sectional view illustrating a primary part of this structure. As illustrated in FIGS. 25 and 26, a room lamp 57 and a spotlight 58 are lamp units respectively mounted in lamp mounting windows 55 and 56 opened in a roof trim 53 serving as an interior wall member that covers a body roof 52.
As shown in FIG. 25, a flat cable harness 51 fixed too circuit elements to an insulating sheet is wired between the room lamp 57 and the spotlight, so that the room lamp 57 and the spotlight 58 are integrally formed to constitute a roof harness 50.
Thus, since the components to be roof-mounted, such as the room lamp 57, the spotlight 58, the rearview mirror (not shown), and a sun visor, on the roof trim 53 is preliminarily assembled to form a roof module and then the module is mounted on the body roof 52, an operation of mounting components on the roof trim 53 can be omitted when a low-workability roof trim is mounted, thereby facilitating an assembling operation.
Meanwhile, according to the related automobile roof assembling method illustrated in FIGS. 23 and 24, for example, when the aforementioned related room lamp 35 is mounted onto the roof trim 30, it is necessary to temporarily and downwardly draw the connector 40 connected to the cable 37a of the roof harness 37 from the room lamp mounting window 31a and to then connect the connector 4 to a room-lamp-side connector 45 of the room lamp 35. Further, upon completion of connecting the connector 4 thereto, it is necessary to place the connectors 40 and 45 on the roof trim 30 together with the cable 37a of the roof harness 37 through the lamp mounting window 31a and to then fix the room lamp 35 to the lamp mounting window 31a by using the tapping screw 42. This complicates the assembling operation that is overhead work performed in a narrow working space. Consequently, good workability is difficult to obtain.
Thus, the module is preliminarily formed by mounting the components to be roof-mounted, such as the room lamp 35, the map lamp 36, the rearview mirror 38, and the sun visor 39, onto the roof trim 30. Then, the module is mounted on the body roof 2. Consequently, the operation of mounting the components on the roof trim can be omitted. This facilitates the assembling operation.
However, when the module is mounted thereon, the body roof trim 30 covers and hermetically seals the bottom-side portion of the body roof 2, so that an enclosed chamber is formed therein. Therefore, the connectors 40 and 41 placed in the enclosed chamber cannot be connected to the room lamp 35 and the map lamp 36. Thus, the following method is considered. The connectors 40 and 41 at the side of the body roof 2 are fixed, as employing reception connectors, at places respectively portions corresponding to the room lamp 35 and the map lamp 36 at the side of the module, simultaneously with the mounting of the module thereon. However, the mounting accuracy of the module (or the roof trim 30) is significantly low, as compared with the connecting accuracy of the connectors 40 and 41. Actually, it is difficult to connect the connectors 40 and 41 to the connector portions with good accuracy. Especially because of the fact that the connection states of the connectors 40 and 41 cannot be visually checked by a worker, this conventional method has encountered a problem of poor connection reliability.
Further, the room lamp 35 has a lamp function portion, that is, comprises a portion that the housing 34, the tapping screw 42, the bus bar 43, the bulb 44, the connectors 40, 45 and the switch unit, as described above. Thus, the number of components of the functional portion of the room lamp 35 is large. When the reflector is attached thereto, the number of components thereof increases still more.
Further, as the manufacturing costs of the components increase, the assembling thereof is complicated more and more. Consequently, it is difficult to reduce the manufacturing cost of the lamp unit.
On the other hand, in the case of the related lamp unit mounting structure illustrated in FIGS. 25 and 26, when a roof module obtained by preliminarily inserting the room lamp 57 and the spotlight 58 into the lamp mounting windows 55 and 56 of the roof trim 53 is mounted onto the body roof 52, the roof trim 53 is assembled and fixed to the body roof 52, as shown in FIG. 26. Simultaneously, the room lamp 57 is screwed into and fixed to the body roof 52. Moreover, the room lamp 57 is fitted into the opening formed in the body roof 52. Thus, the lamp unit is mounted onto the roof trim.
Thus, in the case that the roof trim 3, whose mounting accuracy is poor, causes positional displacement with respect to the body roof 52 when the roof trim (or roof module) 53 is assembled to the body roof 52 in a vehicle body assembly line, the room lamp 57 inserted into the lamp mounting window 55 of the roof trim 53 causes positional displacement with respect to the screw holes and the openings provided in the body roof 52. Thus, there is a possibility that the room lamp 57 cannot be mounted onto the body roof 52.
Further, even when the room lamp 57 is mounted thereon, a gap S is provided between the peripheral edge of the cover lens of the room lamp 57 and the periphery of the lamp mounting window 55 so that the width of the gap S is equal to an amount of positional displacement of a center mounting axis O1 of the room lap 57 mounted on the body roof 52 with respect to a center axis O2 of the opening, that is, the lamp mounting window 55, as illustrated in FIG. 26. This deteriorates the appearance of the lamp unit. Thus, this related mounting structure has encountered another problem of degradation in quality of the lamp unit.
That is, the related mounting structure for the lamp unit illustrated in FIG. 25 has encountered problems that the assembling workability at the assembling of the roof trim 53 and the body roof 52 is not good, and that an assembling failure is liable to occur.
Accordingly, an object of the invention is to solve the aforementioned problems and to provide a lamp unit assembling method and a lamp unit mounting structure, which facilitate an operation of assembling a lamp unit and enable reliable connection of cables and construction of a high-quality lamp unit.
To achieve the foregoing object, according to a first aspect of the invention, there is provided a lamp unit assembling method (hereunder referred to as a first assembling method), which comprises the steps of fixing connection portions of cables to cable connecting portions of a lamp unit, and subsequently mounting the lamp unit in a lamp mounting window provided in an interior wall member and arranging the cable on a vehicle body panel side portion of the interior wall member to thereby construct a module, and assembling the module in such a way as to cover a vehicle body panel.
According to a second aspect of the invention, there is provided a lamp unit mounting structure (hereunder referred to as a first mounting structure) for mounting a lamp unit in a lamp mounting window provided in an interior wall member covering a vehicle body panel. The lamp unit consists of a design portion and a functional portion. A connection portion of a cable to be arranged on a vehicle body panel side portion of the interior wall member is fixed to a cable connecting part of the functional portion.
According to a third aspect of the invention, there is provided a lamp unit mounting structure (hereunder referred to as a second mounting structure) for mounting a lamp unit in a lamp mounting window provided in an interior wall member covering a vehicle body panel. The lamp unit consists of a design portion and a functional portion. The functional portion comprises a reflector, which is integrally formed from an electrically conductive material and provided with one of bulb contacts, and a switch unit that accommodates a switch circuit and has the other of the bulb contacts. A connection portion of each of cables to be arranged on a vehicle body panel side portion of the interior wall member is fixed to a cable connecting portion of a corresponding one of the reflector and the switch unit.
According to a fourth aspect of the invention, there is provided a lamp unit mounting structure (hereunder referred to as a third mounting structure) for mounting a lamp unit in a lamp mounting window provided in an interior wall member covering a vehicle body panel. The lamp unit comprises a functional portion, which has a switch unit, and a design portion latching a switch knob slidably. The functional portion is mounted on the vehicle body panel in such a way as to be able to perform relative displacement only along a direction, in which the switch knob slides, and also mounted in the lamp mounting window of the interior wall member in such a manner as to be able to perform relative displacement at least along a direction perpendicular to the direction in which the switch knob slides. The design portion is fixed from an indoor side in the lamp mounting window provided in the interior wall member. A switch lever of the switch unit engages with an engaging portion of the switch knob in such a way as to be able to perform relative displacement only in a direction perpendicular to the direction, in which the switch knob slides, and is operated by the switch knob.
According to a fifth aspect of the invention, there is provided a lamp unit mounting structure (hereunder referred to as a fourth mounting structure) for mounting a lamp unit in a lamp mounting window provided in an interior wall member covering a vehicle body panel. The lamp unit comprises a functional portion thereof, which has a switch unit, and a design portion latching a switch knob slidably. The functional portion is elastically supported in the lamp mounting window of the interior wall member in such a manner as to be able to perform relative displacement at least along a direction in which the switch knob slides. The design portion having a position regulating member for restricting relative displacement of the switch knob along the direction, in which the switch knob slides.
According to the first assembling method, and the first and second mounting structures, each of the connection portions of the cable to be preliminarily arranged on the interior wall member is fixed to a corresponding one of the cable connecting portions of the lamp unit (that is, the functional portion). When the cable is arranged on the interior wall member, the lamp unit (that is, the functional portion) is simultaneously mounted in the lamp mounting window.
Thus, the lamp unit (that is, the functional portion) and the cable are put into a state, in which the lamp unit (the functional portion) and the cable are electrically connected to each other, without using the connectors. Further, the lamp unit (that is, the functional portion) and the cable, which are in such a state, and the interior wall member are integrally formed and modularized. Then, an assembling operation is completed only by assembling a module, which is formed so that the lamp unit (that is, the functional portion) and the cable are integral with the interior wall member, to the vehicle body panel.
Further, the electrical connection between the lamp unit (that is, the functional portion) and the cable is established by a worker who visually checks the connection state thereof and fixes the cable to the lamp unit (that is, the functional portion) by working in a downward posture. Thus, high reliability of the connection therebetween is obtained, regardless of the accuracy of mounting of the interior wall member onto the vehicle body panel.
Incidentally, preferably, in an embodiment of the first assembling method, the first mounting structure, or the second mounting structure, a cable fixing member for fixing the cable to the functional portion thereby to prevent a pulling force from acting upon the connection portion of the cable is provided in the vicinity of the connection portion.
In this case, a part, which is close to the connection portion, of the cable is fixed by the cable fixing member (that is, the functional portion). Thus, the fixed part is reliably prevented from being disconnected from the lamp unit by a pulling force that is generated due to oscillations caused when the cable is arranged on the interior wall member or when the vehicle runs, and that acts upon the connection portion of the cable.
Further, according to the first mounting structure, even when the functional portion fixed to the connection portion of the cable is transported together with the cable and mounted on the interior wall member, the design portion is prevented from being flawed by being brought into contact with other members.
Moreover, even in the case that the design portions of the lamp units differ from each other according to the types of vehicles, the functional portion may be employed in common by the lamp units. Thus, it is sufficient to change only the design portion so as to manufacture the lamp units.
Incidentally, preferably, in the case of an embodiment of the first mounting structure, when a switch lever of the functional portion is latched by the design portion, and the design portion is assembled to the functional portion, the switch lever is operated by a switch knob engaging with the switch lever.
In this case, even when the switch knob of the lamp unit change according to the typed of the interior, the functional portion may be employed in common by the lamp units. Thus, it is sufficient to change only the switch knob according to the predetermined color and shape. Furthermore, the engagement between the switch knob and the switch lever can be performed simultaneously with the assembling of the design portion to the functional portion, so that the number of man-hours needed to perform the assembling operation does not increase.
Further, according to the third mounting structure, a bulb (that is, an electric bulb) is mounted between one of the bulbs, which is provided in the reflector that is integrally formed from the electrically conductive material and that serves as a circuit conductor, and the other bulb contact of the switch unit. Moreover, the connection portion of each of the cables is directly fixed to the cable connecting portion of a corresponding one of the reflector and the switch unit of the functional portion. This eliminates the necessity for providing conductors, such as a bus bar, and connector portions in the functional portion in such a way as to be separated from one another. Consequently, the number of components is reduced, as compared with that of components of the conventional lamp unit.
Incidentally, preferably, in an embodiment of the second mounting structure, the cable connecting portion of the reflector is provided in the vicinity of the cable connecting portion of the switch unit so that the cable connecting portions of the reflector and the switch unit are placed in juxtaposition with each other. Thus, the cable connecting portions, to which the connection portions of the cables are fixed, are put together at one place.
Operations of fixing the cables are collectively performed at this place. This enhances workability and increases flexibility in designing wiring paths.
Further, preferably, in an embodiment of the second mounting structure, the reflector has a latching member enabled to be caught in the lamp mounting window. Thus, when the module is formed by preliminarily assembling the functional portion to the interior wall member, the assembling operation is facilitated still more.
Moreover, preferably, in an embodiment of the second mounting structure, the reflector has a cable holding portion for guiding and holding the cable arranged along an outer side surface of the reflector. Thus, when the functional portion is mounted in the lamp mounting window of the interior wall member, the biting of the cable is prevented.
According to the third mounting structure, the functional portion to be connected to each of the cables preliminarily arranged on the interior wall member is mounted in such a manner as to be able to perform relative displacement at least along a direction perpendicular to the direction in which the switch knob slides. Moreover, the design portion is fixed from an indoor side in such a manner as to cover the lamp mounting window.
At that time, the switch lever of the switch unit engages with the engaging portion of the switch knob slidably caught in the design portion, and is enabled to be operated by the switch knob.
Further, the lamp unit consisting of the functional portion and the design portion is formed in such a way as to be integral with the interior wall member and to be modularized before assembled to the vehicle body panel.
Subsequently, when the interior wall member formed in such a way as to be integral with the lamp unit is assembled to the vehicle body panel, the functional portion is simultaneously mounted on the vehicle body panel in such a way as to be able to perform relative displacement along the direction in which the switch knob slides.
Thus, when the interior wall member assembled to the vehicle body panel causes positional displacement with respect to the vehicle body panel along the sliding direction in which the switch knob slides, the functional portion can perform relative displacement with respect thereto along the sliding direction together with the interior wall member. Consequently, the functional portion is mounted on the vehicle body panel by absorbing the positional displacement caused along this sliding direction.
On the other hand, when the interior wall member assembled to the vehicle body panel causes positional displacement with respect to the vehicle body panel along a direction perpendicular to the sliding direction in which the switch knob slides, the functional portion can perform relative displacement with respect thereto along the sliding direction together with the interior wall member. Consequently, the functional portion is mounted on the vehicle body panel by absorbing the positional displacement caused along the direction perpendicular to the sliding direction.
Therefore, an assembling failure disabling the mounting of the lamp unit is prevented from occurring owing to the positional displacement caused at the time of assembling the interior wall member to the vehicle body panel. Consequently, the functional portion is easily assembled to the vehicle body panel by simultaneously performing aligning.
Furthermore, the design portion is fixed in the lamp mounting window of the interior wall member from the indoor side independent of the functional portion. Thus, the design portion is mounted at the predetermined place regardless of the positional displacement of the interior wall member with respect to the vehicle body panel. Consequently, the appearance of the lamp unit is not deteriorated by the mounting state of the interior wall member, so that the quality of the lamp unit is enhanced.
Further, as described above, when the functional portion absorbs the positional displacement caused in the direction perpendicular to the sliding direction in which the switch knob slides, the functional portion performs positional displacement with respect to the interior wall member. However, the switch lever engages with the engaging portion of the switch knob in such a way as to be able to perform positional displacement in the direction perpendicular to the sliding direction in which the switch knob slides. Thus, the engagement between the switch lever and the switch knob is established without hindrance.
Conversely, when the functional portion absorbs the positional displacement caused along the sliding direction in which the switch knob slides, the functional portion performs relative displacement together with the switch knob fixed to the interior wall member. Thus, the switch lever does not need to engage with the engaging portion of the switch knob. Consequently, the switch lever is enabled to minimize the gap in the sliding direction between the switch lever and the engaging portion of the switch knob. The operating range of each of the switch lever and the switch knob does not change according to the mounting state of the interior wall member to the vehicle body panel.
According to the fourth mounting structure of the invention, the functional portion, which is connected to each of the cables preliminarily arranged on the interior wall member, is elastically supported in such a way as to perform positional displacement at least along the sliding direction, in which the switch knob slides, with respect to the lamp mounting window of the interior wall member. Thus, the functional portion is mounted without backlash by simultaneously aligning. Consequently, the assembling of the functional portion is facilitated.
Further, when the design portion is fixed from the indoor side in such a way as to cover the lamp mounting window, the position regulating member of the design portion engages with the functional portion and regulates the relative displacement caused along the sliding direction in which the switch knob slides. When the switch lever of the switch unit of the functional portion is engaged with the engaging portion of the switch knob that is slidably caught by the design portion, the switch lever is enabled by the switch knob to operate.
Thus, the movement of the functional portion, which is caused in response to an operation of the switch knob, is restricted. Therefore, although the functional portion is elastically supported against the lamp mounting window, so that the assembling of the lamp unit is easily performed, the operability of each of the switch knob and the switch lever is enhanced. Further, the quality of the lamp unit is improved.
Incidentally, preferably, in an embodiment of the third mounting structure or the fourth mounting structure, the design portion has a temporally latching member for temporarily latching the switch knob at a predetermined place in such a way as to disable the switch knob from sliding.
In this case, in a state in which the switch knob is temporarily fixed at the predetermined place in such a way as to disable the switch knob sliding, the design portion is fixed from the indoor side in such a manner as to cover the lamp mounting window. Thus, the switch lever of the functional portion is reliably engaged with the engaging portion of the switch knob, which is slidably engaged with the design portion. Therefore, a worker does not need to perform aligning so as to simultaneously fix the design potion to the interior wall member.
This facilitates the assembling of the lamp unit and the reliable engagement of the switch lever with the engaging portion of the switch knob. Consequently, an occurrence of an assembling failure is prevented. Moreover, the quality of the lamp unit is improved.
Furthermore, preferably, according to an embodiment of the third mounting structure or the fourth mounting structure, the engaging portion of the switch knob has a latching member for enabling the switch lever to be inserted along the sliding direction in which the switch knob slides.
In this case, the latching member of the engaging portion of the switch knob enables the switch lever to be inserted along the sliding direction only by performing a sliding operation on the switch knob, which is latched by the design portion, after the design portion is fixed to the interior wall member in such a manner as to cover the lamp mounting window. Thus, the switch lever is reliably engaged with the engaging portion of the switch knob.
Consequently, a worker does not need to perform aligning so as to simultaneously fix the design potion to the interior wall member. This facilitates the assembling of the lamp unit and the reliable engagement of the switch lever with the engaging portion of the switch knob. Thus, an occurrence of an assembling failure is prevented. Moreover, the quality of the lamp unit is improved.